fix: 修复统计图表不显示与对比上月Infinity问题

- ChartWrapper: 添加 type 属性修复 uCharts 不渲染
- ChartWrapper: 使用 pixelRatio=1 避免双重缩放导致字体线条过大
- ChartWrapper: 统一 fontSize/fontColor/padding 配置
- ChartWrapper: 挂载时保存实例引用避免异步回调中 getCurrentInstance 返回 undefined
- stats: Number() 强制类型转换避免字符串导致 Infinity
- stats: !prev 宽松判断覆盖 null/undefined/0 除零情况
- stores: fetchOverview/fetchCategoryStats/fetchTrend 确保数据字段为数字

client/src/stores/stats.ts

@@ -15,7 +15,14 @@ export const useStatsStore = defineStore('stats', () => {
 
   async function fetchOverview(month?: string) {
     try {
-      overview.value = await api.getOverview({ month: month || getCurrentMonth() })
+      const data = await api.getOverview({ month: month || getCurrentMonth() })
+      // 确保数据字段是数字类型
+      overview.value = {
+        expense: Number(data?.expense) || 0,
+        income: Number(data?.income) || 0,
+        count: Number(data?.count) || 0,
+        daily: Number(data?.daily) || 0
+      }
     } catch {
       overview.value = { expense: 0, income: 0, count: 0, daily: 0 }
     }
@@ -23,7 +30,13 @@ export const useStatsStore = defineStore('stats', () => {
 
   async function fetchCategoryStats(month?: string, type: string = 'expense') {
     try {
-      categoryStats.value = await api.getCategoryStats(month || getCurrentMonth(), type)
+      const data = await api.getCategoryStats(month || getCurrentMonth(), type)
+      // 确保返回的是数组，且金额是数字
+      categoryStats.value = Array.isArray(data) ? data.map(item => ({
+        ...item,
+        amount: Number(item.amount) || 0,
+        count: Number(item.count) || 0
+      })) : []
     } catch {
       categoryStats.value = []
     }
@@ -31,7 +44,12 @@ export const useStatsStore = defineStore('stats', () => {
 
   async function fetchTrend(month?: string, type: string = 'expense') {
     try {
-      trendData.value = await api.getTrend(month || getCurrentMonth(), type)
+      const data = await api.getTrend(month || getCurrentMonth(), type)
+      // 确保返回的是数组，且金额是数字
+      trendData.value = Array.isArray(data) ? data.map(item => ({
+        ...item,
+        amount: Number(item.amount) || 0
+      })) : []
     } catch {
       trendData.value = []
     }